1. Field of the Invention
The system of the present invention relates to oil well drilling and production. More particularly, the present invention relates to a system for monitoring both the direction of a drill string and the number of revolutions made by the drill string over a given time during back off or fishing operations.
2. General Background of the Invention
In the present state of the art, in the drilling of oil wells and the production of hydrocarbons, there are many tasks which have to be undertaken during the rather complex process, which requires that the operator of the rig know at all times certain features of the string. For example, during back off of the drill string during drilling, it is necessary that the number of revolutions that the drill string makes during the back off be monitored very carefully so as to be able to calculate the proper amount of torque that is needed during the back off work. Secondly, it is important that the operator on the rig floor know the direction i.e. clockwise or counter-clockwise that the drill string is rotating during operations such as back off work, or during fishing operations.
One of the more common systems of counting the revolutions that a drill string makes is to simply tie a piece of cloth or the like on the drill pipe or on the kelly and as the kelly rotates, the cloth would strike a worker or the like on the leg and the worker would keep count of the number of revolutions made during a particular given time. Although this is a quite primitive way of counting revolutions, it is often the only manner of counting revolutions of a drill string that it is used in such a system.
Therefore, there is a need in the art for a system that is able to be a reliable yet precise system of counting the revolutions made by, for example, a drill pipe during operations conducted on a rig, and to sense the direction that the drill pipe is rotating so as to ascertain whether the drill string is turning clockwise or counter-clockwise as the case may be.
In a search conducted of the art in this field, there are several patents which were found that may be pertinent to the art and these patents are included herewith in a prior art statement submitted with this patent application.